Torque measuring device



Dec. 30, 1952 l G, E, JAM|ESQN 2,612.3,385l

TORQUE MEASURING DEVICE Filed Nov. 6, 1948 TMR SUPPLY Fig. 4.

Inventor; GilbertBJameson,

u by

His Att Orwey.

Patented Dec. 30, 1952 42,623,385 rroRQUE MEASURING DEVICE GilbertE. Jamieson, Fort 'Wayne Ind., -assignor to General Electric Company, a

corporation of Application November 6. iefigseriamb. 58,697

4 claims. (o1. '1s-136) This invention relates to` torque measuring devices for rotating machines. I

In the testing of rotating machines such as generators,`motors, and other rotating sources of mechanical power, `it is desirable to provide a simple device for measuring the torque output of the machine. Such a torque measuring device shouldl be so constructed as to permit ready mounting and dismounting thereon of the Another object of this invention is to provide an improved direct reading torque measuring device forfrotating machines.

Further objects and advantages of this inventionwill become apparent and the invention will be better understood by reference to the following description and the accompanying drawing. The features of novelty which characterize this invention will be pointed out with particularity inthe claimsannexed to and forming a part of this specification. I 1

In accordance with this invention, there is provided a torque `measuring device for rotating machines having a base member adapted to have the machine to be tested mounted thereon. The basei member is supported at one end by two `hinges and at the other end by a force measuring device such as a pressure cell. `The axis of the hinges is parallel with "the: axis off the shaft of the test machine, and the two hinges and the pressure cell form a three point support for the basemember. When a load is placed on the test machinethe reaction torqueexerted on itsstationary member is transferred to the base mem.- ber which tends to rotate about the hinged points of suspension exerting a force on the pressure cell. Thus, the pressure cell can be Vcalibrated in terms of torque as determined b-y the length of the lever arm from the hinges to the point of engagement of the pressure cell with the base member.

Referring now to the drawing, Fig. 1 is a side elevational view of the improved torque measuring device of this invention; Fig. 2 is a vertical view of the device of Fig. 1; Fig. 3 shows the use of a double-acting pressure cell instead of the single-acting pressure cell of Figs. 1 and 2; Fig. 4 shows the use of an anti-friction bearing hinge instead of the strip hinges of Figs. 1 and 2; Fig. 5 is a vertical view, partly in section, of the hinge mechanism of Fig. 4; and Fig. 6 is a side eleva-A tional View of a modication of this improved torque measuring device.

nReferring now toFigs. 1 and 2, there is shown a `Ushaped basemembe'r or cradle I which may be conveniently formed of fabricated steel with a lower` portion 2, and leg portions 3 and 4 joined together by welds at'E and 6. The leg 3 is pro-` vided with two` projections 1 at its outer edge secured `byl welds BQ The-projections TI of the base member I are supported by a stationary supporting member 9 through striphinges Il] which` comprise a thin ilexible s trip` of metal II secured tothe supporting member 9 and the projections 'Isin any suitable manner, as byf bolts yI2.` The leg 1it of the base member I has a projection I3 at its outer edge secured by a weld I4. The projection"l3 is supported by va suitableforce` measj uring device such as' a `pressure cell I5 which engagesthelovwer edge of the projection I3 as at I6. A supply of air is provided for the pressure cell I5 from a line I1 andtheforce exertedon the, pressure cell I5 is ,rneasured in anysuitable manner, as a manometer or gauge I 8.. The

,test dynamoelectric machineY I9 is mountedon the lower portion 2 of the base member Il so that the `axis of the vshaft 2i] isat right angles tothe axis offrthe'hinges Il] and the pressure cell l'.` It willgn'ow be seen that the basemember I .or cradle issupported at three points, namely the two strip hi'ngefsgl I (lon ne side and the pressure cell I5 on 4priere; the dimension 2 Iwbetweenthe hinges IIJ andjthegpointof Vsupport;lifbecomes a phantom lever arrmjNWlien 5a" "loadjis placed on the machinethe reactionlgtorqueexerted on the staf tionarymember 22 is transferredtothe base member [which `tendsto .rotate the base member.

about the hingesll 0 exerting aiorce on the pressurecell I5.`.}The indicator'jl canbe calibrated to read torque directlysince the torque of the machine is the force exerted on the pressure cell times the dimension ZI. Furthermore, the dimension 2| can be varied to provide a convenient constant in the horsepower formula. A slot 23 may be provided at the end of the projection I 3 for use in -calibrating the indicator I8 to adjust the dead weight of the test motor I9 to a suitable value.

If a test generator is rotating in the direction shown by the arrow 24, or a test motor is rotating in the direction shown by the arrow 215, a singie acting pressure cell, as shown in Fig. 1, is satisfactory since the force exerted on the pressure cell will always be in the downward direction. However, if the direction of rotation is as shown by the arrow 25 for a generator, or arrow 24 for a motor. the force will be in the upper direction and in the event that the upward force exceeds a certain percentage of the dead weight of the machine, determined by the position of the center line of the shaft 20 with respect to the hinges I and the point of contact I6, a double acting pressure cell must be utilized as shown in Fig. 3. Here, the projection I3 is engaged by two pressure cells 26 and 27 -which are fed by the common air supply line I'I and which are connected to the indicator I8. With this double acting pressure cell arrangement, the torque measuring device of Fig. 1 can be utilized with motors or generators operating in either direction of rotation.

In the event that the total movement of the projection I3 is greater than approximately .010 inch, it will be found desirable to use antiiriction bearing hinges as shown in Figs. 4 and 5, rather than strip hinges as shown in Figs. 1 and 2. Here, the projections l are formed with a projection 28 to which an inner bearing race 29 is secured. An outer bearing race 30 is positioned in a mounting member 3i which is in turn secured to the stationary supporting member 9 in any suitable manner, as by bolts 82. A plurality of balls 33 are interposed between the inner race 29 and the outer race 30. Furthermore, if the total movement of the projection I3 is to be more than approximately .010 inch, it may also be desirable to use a different type of force measuring device, such as an automatic scale as shown at 34, rather than a pressure cell.

Referring now to Fig. 6, there is shown a modication of this improved torque measuring device wherein there is provided a straight base member 35 rather than the U-shaped base member I of Fig. 1. Here, the test machine I9 may be mounted above the base member 35, as shown, or below the base member 35. As in the embodiment of Fig. 1, the dimension 2l between the hinges I and the point of support It is a phantom lever arm and the indicator I8 can be calibrated to read the torque of the motor directly.

It will now be readily seen that this invention provides an improved and greatly simplied form of torque measuring device wherein a test motor or generator can be readily mounted in and dismounted from the base member and which provides a direct reading of torque. While a dynamo-electric machine is schematically shown in the drawing, it will be readily understood that any other rotating source of mechanical power, or other rotating device requiring power to drive it, can be tested with this device, such as an internal combustion engine, or a pump.

While there are shown and described specific embodiments ofthis invention, further modifications and improvements will become apparent to those skilled in the art. I desire that it be understood, therefore, that this invention is not to be limited to the particular arrangement disclosed and I intend in the appended claims to cover all modifications which do not depart from the spirit and scope of this invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

l. For use with a rotating machine comprising mechanical or electrical power producing means having a shaft and a relatively stationary `member having supporting feet extending below and on either side of said shaft, a torque measuring device comprising an upright U- shaped base means for mounting said feet on the lower portion of said U-shaped base, whereby the U-A-shaped member absorbs reactive torque from the stationary member of said machine, means hinging one of the upper ends of said U-shaped member to a fixed support about an axis parallel to said shaft at substantially the same height as said shaft and at one side of said machine, and force measuring means supporting the other upper end of said U-shaped member at substantially the same height as said shaft and at the opposite side of said machine.

2. The combination as in ,claim 1 further characterized by said hinge means comprising a pair of hinges spaced parallel to the axis of said shaft.

3. 'I'he combination as in claim 1 further characterized by said hinge means comprising a pair of antifriction bearings spaced parallel to the axis of said shaft.

4. The combination as in claim 1 further characterized by said force measuring means comprising at least one pressure cell adapted to support the associated end of said U-shaped base member.

GILBERT E. J AMIESON REFERENCES CITED The following references are of record in the 

